Answer to Question #339338 in General Chemistry for asi

Question

Calculate the reaction entropy (S°rxn) for the following reaction: 3 NO₂ + H₂O 2 HNO₃ + NO

Answer 1

ΔS°_rxn = ΔS(NO) + 2ΔS(HNO₃) - 3ΔS(NO₂) - ΔS(H₂O)

ΔS°_rxn= 210.65 + (2 × 155.6) - (3 × 239.9) - 69.94 = 210.65 + 311.2 - 719.7 - 69.94 = 521.85 - 789.64 = -267.79 J/K (decrease in entropy)